1. Field of the Invention
The present invention relates to communication, and more specifically to a method for saving power of a station in the wireless network.
2. Description of the Prior Art
Wireless networks are widely deployed to provide various communication services such as video, voice, broadcast, messaging, etc. These wireless networks may be capable of supporting communication for multiple users by sharing the available network resources. Examples of such networks include wireless local area networks (WLANs), wireless metropolitan area networks (WMANs), wireless wide area networks (WWANs), and wireless personal area networks (WPANs).
A wireless network may include any number of access points (APs) and any number of stations. An access point may act as a coordinator for communication with the stations. A station may actively communicate with an access point, may be idle, or may be powered down at any given moment depending on the data requirements of the station.
For a station operating in a power saving mode, when no packet is received or transmitted (hereinafter referred to as a sleep period), components of the station are turned off to reduce current consumption. In order to receive a scheduled packet, components of the station are wakening up before the scheduled packet arrives. For example, during a sleep period, most components, except a GPIO device, of the station are turned off to reduce current consumption.
Because current handheld stations, such as wireless handheld device, are powered by batteries, power saving has always been the primary issue concerned. Proper sleep periods help prolong powered time and battery life.
IEEE 802.11 is a family of standards developed by The Institute of Electrical and Electronics Engineers (IEEE) for WLANs. IEEE 802.11 defines a method for a station to sleep and thus save power. However, the efficiency of the method is limited for stations desiring very low power consumption because of signaling limitations in the standard as well as limited support by the access points and/or stations.
There is therefore a need in the art for techniques to improve the sleep period of a station in a wireless network.